For now: drop `diffNode` - inlining it into `diff()` doesn't cause a de-opt and saves 11b.
For now: drop `diffNode` - inlining it into `diff()` doesn't cause a de-opt and saves 11b.

developit/preact,gogoyqj/preact,neeharv/preact,developit/preact,neeharv/preact